This disclosure relates generally to fastening devices and, more particularly, relates to a heat sink fastening device. As computer technology continues to advance, electronic components such as central processing units (CPUs) of computers are being made to provide faster operational speeds and greater functional capabilities. When a CPU operates at a high speed in a computer enclosure, its temperature can increase rapidly. It is desirable to dissipate the generated heat of the CPU quickly, for example, by using a heat sink attached to a surface of the CPU. This allows the CPU and other high-performance electronic components in the enclosure to operate within their normal operating temperature ranges, thereby assuring the quality of data management, storage and transfer for the CPU. Oftentimes, fastening devices are required for mounting the heat sink to, for example, the CPU. The fastening devices and the heat sink may be pre-assembled together before the heat sink is finally mounted to the electronic component in order to facilitate mounting of the heat sink by end users. The end users can be asked to manually manipulate the fastening device to mount the heat sink.